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feet Soil samples from the soil bores were extracted at five foot intervals from a depth of ten feet to sixty <br /> . feet (see site map for location attached) All three soil bores produced samples above detection levels <br /> for BTEX and TPHg and TPHd (see Soil Sample Recap Attached) <br /> Monitoring Wells MW#4S and MW#4D were installed on the east side of Wilson Way in September of <br /> 2000 Also,monitoring wells MW#5D,MW#6S and MW#6D,MW#7S and MW#7D were installed north <br /> and south of the pump islands in September of 2000 (see attached Site Map) <br /> Monitoring wells MW#8S aitd MW8D were installed in a single bore hole inside the existing building, <br /> west of the pump islands on October 3, 2000 <br /> SECOND QUARTER 2002 MONITORING WELL SAMPLE ANALYSIS REPORT <br /> Sampled 06/10/02 <br /> WATER ANALYSIS OF SAMPLES FROM MONITORING WELLS <br /> On Tune 10, 2002, Del-Tech Geotechnical Support Services extracted water samples from each <br /> monitoring well using standard industry practices under the supervision of Foothill Engineering A report <br /> of this work by Del-Tech Geotechnical Support Services is attached and is a part of this report The water <br /> samples were transported on ice by chain of custody to Sherwood Labs for analysis by Method SW8020F <br /> for BTEX, and TPHg Samples of each set of groundwater extractions were forwarded to Entech <br /> Analytical Labs of Santa Clara, Ca for analysis by EPA Methods 8260FA Entech failed to analyze for <br /> dissolved lead as directed by the chain of custody As result, dissolved lead results are not listed in the <br /> Water Analysis Recap attached <br /> FINDINGS FROM GROUNDWATER SURFACE DETERMINATION <br /> The groundwater elevation on this site has dropped about 2 8'from the measurements done on February <br /> 13, 2002 and is about 7 5' lower than in the first quarter of last year The slope of the groundwater <br /> gradient for this event is down slope to the northeast at S = 0 001 <br /> FINDINGS FROM MONITORING WELL SAMPLE ANALYSIS FOR BTEX AND TPHg <br /> The concentration ofTPHg in monitoring well MW#2 has risen from the last event All other monitoring <br /> points are lower for TPHg than last quarter MW#4D, MW#4S, MW#5D, MW#6D, and MW#7D are <br /> below detection levels for TPHg this quarter <br /> FINDINGS FROM MONITORING WELL SAMPLE ANALYSIS FOR OXYGENATES <br /> At the request of the PHSIEHD,samples from this event were analyzed for oxygenates by EPA method <br /> 8260FA including 1,2-Dichoroethane and 1,2-Dibromoethane Groundwater samples from MW#1, <br /> MW#2, MW#5D, MW#7D,MW#8D, and MW#8S contained 1,2-Dichoroethane in concentrations up <br /> to 1500 uglL The groundwater samples were analyzed for 1,2-Dibromoethane and all monitoring points <br /> were below detection levels <br /> CONCLUSIONS <br /> The water table elevations on this site continue to fluctuate <br /> High volume agricultural pumping offsite most likely is the reason for this large variation in water <br /> surface elevations Concentrations of TPHg have continued fluctuating with the rise and fall of the <br /> groundwater elevation High groundwater elevations yield the highest concentrations <br /> 2 <br />